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From: Jannel Rémi (remj_at_[hidden])
Date: 20050202 04:20:29
Hello All,
I started to use boost a few weeks ago and i still have got some problems with the graph_traits theory. In fact, it seems that you use a graph_traits to stock the type of the data used for the Graph (given as a template) such as vertex_descriptor or in_edge iterator.
To keep this you use something like:
typedef typename Graph::vertex_descriptor vertex_descriptor;
which means that you get this type from Graph::vertex_descriptor.
Now, if i want to wite an algorithm which will search for all the vertices for example, i'll have to use my Graph as a template and i'll get the vertex type for example using
typedef typename graph_traits<Graph>::vertex_descriptor vertex_descriptor;
That's why I wanted to ask you why this method is used instead of just
typedef typename Graph::vertex_descriptor vertex_descriptor;
used in the class graph_traits definition.
I hope i made me understandable!
Thanks a lot
Koopajah
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